The present invention relates to a method and a device for controlling a vehicle.
In modern vehicle control systems, multiple, and sometimes contradictory, selections may act on actuators (e.g., drive unit, transmission, etc.). Thus, for example, the drive unit of a motor vehicle may be controlled on the basis of a driving intent selected by the driver, and setpoints of external and/or internal regulation and control functions, such as a traction control, an engine anti-slip control, a transmission control, a speed limiter, and/or an idle speed regulator. These setpoint selections may have opposing effects, so that, since the drive unit may only achieve one of these setpoint selections, these setpoint selections must be coordinated, i.e., one setpoint selection to be implemented is to be selected.
A coordination of various torque setpoints in connection with the control system of a drive unit is referred to in German Published Patent Application No. 197 39 567, in which a setpoint is selected from the torque setpoints through maximum and/or minimum value selection, which is implemented in the instantaneous operating state by determining the variables of the individual control parameters of the drive unit, for example, in an internal combustion engine, the filling, the firing angle, and/or the quantity of fuel to be injected. In addition to the variables of the setpoint selections, various characteristics may be connected to the setpoint selections, for example, in relation to the required dynamic response of the adjustment, the priority, etc., which may also be of contradictory nature and which may not be considered in the coordination of the setpoint selections.
A procedure is referred to in German Published Patent Application No. 197 09 317, in which coordinators are selected for an entire vehicle. These coordinators perform the resource requirements and the resource distribution of the control systems of the entire vehicle on the basis of communicated boundary conditions, for example, a desired dynamic response. Concrete information concerning the procedure for controlling a drive unit may not be provided in consideration of the characteristics of the setpoint selections described above.
It is an object of an exemplary embodiment according to the present invention to provide measures that, in addition to the setpoint selection variables, aid in the coordination of the characteristic variables connected with them and/or consider the characteristic variables for control of the drive unit, upon conversion of the characteristic variables into control variables.
By coordinating the characteristic variables and the setpoint selection variables independently from one another, optimum coordination of opposing requirements in the control of the drive unit may result, and one suitable setpoint variable at a time, having a selected characteristic variable or selected characteristic variables, is converted into the corresponding control parameter of the drive unit, resulting in an implementation of the setpoint selections within the framework of boundary conditions communicated using the setpoint selections.
It is believed to be advantageous in that coordination of the variables occurs without concrete selection of the control parameters of the drive unit (for example, in an internal combustion engine, filling, firing angle, injection quantity, injection time, etc.) being performed at the time of the coordination of the setpoint selection variables and their characteristic variables.
It is believed that the procedure described above may advantageously coordinate and/or convert setpoint selection variables and characteristic variables in gasoline direct injection systems and in conventional intake manifold injection systems, diesel injection systems, or alternative drive systems (electric drives, fuel cell drives, etc.).
In a torque-oriented control system for the drive unit, external and internal torque requests, including their communicated boundary conditions, are coordinated and prioritized. It is believed that the procedure described above advantageously coordinates differing dynamic response requests, limits of the dynamic response conversion being considered by the coordinator. These coordinators may also be distributed over multiple control devices, independently of the partitioning.
The resulting setpoint determined by the coordinator, including the resulting characteristic variable(s), is converted by one or more setpoints for the control paths (control variables) of the drive unit as a function of the operating point and operating state of the drive unit. The communicated characteristic variables), the instantaneous operating state of the drive unit, and selection of the available control paths are considered during the conversion, so that optimum conversion of the resulting setpoint selections occurs in the framework of the resulting characteristic(s) and the present operating state of the engine.